Display screen or portion thereof with transitional graphical user interface



FIG. 1 is a front view of an electronic device having a display screenor portion thereof with transitional graphical user interface showing afirst image of a first embodiment of our new design;

FIG. 2 is a second image thereof;

FIG. 3 is a third image thereof;

FIG. 4 is a fourth image thereof;

FIG. 5 is a fifth image thereof;

FIG. 6 is a front view of an electronic device having a display screenor portion thereof with transitional graphical user interface showing afirst image of a second embodiment of our new design;

FIG. 7 is a second image thereof;

FIG. 8 is a third image thereof;

FIG. 9 is a fourth image thereof; and,

FIG. 10 is a fifth image thereof.

The evenly spaced broken lines in the drawings show an electronicdevice, a display screen or portion thereof with graphical userinterface elements that form no part of the claimed design.

The appearance of the transitional image sequentially transitionsbetween the images shown in FIGS. 1-5 and 6-10 . The process or periodin which one image transitions to another image forms no part of theclaimed design.

CLAIM The ornamental design for a display screen or portion thereof with transitional graphical user interface, as shown and described. 